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<h2 id="Summary" name="Summary">概述</h2>
<p><code><strong>multiline</strong></code> 属性表明正则表达式是否使用了 "<code>m</code>" 标志。<code>multiline</code> 是正则表达式实例的一个只读属性。</p>
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<th class="header" colspan="2"><code>RegExp.prototype.multiline</code> 属性的属性特性：</th>
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<td>writable</td>
<td>false</td>
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<td>enumerable</td>
<td>false</td>
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<td>configurable</td>
<td>false</td>
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<h2 id="Description" name="Description">描述</h2>
<p><code>multiline</code> 是一个布尔对象，如果使用了 "<code>m</code>" 标志，则返回 <code>true</code>；否则，返回 <code>false</code>。"<code>m</code>" 标志意味着一个多行输入字符串被看作多行。例如，使用 "<code>m</code>"，"<code>^</code>" 和 "<code>$</code>" 将会从只匹配正则字符串的开头或结尾，变为匹配字符串中任一行的开头或结尾。</p>
<p>你无法直接更改此属性。</p>
<h2 id="Examples" name="Examples">示例</h2>
<h3 id="Example:_Using_MIN_VALUE" name="Example:_Using_MIN_VALUE">例子：使用 <code>multiline</code></h3>
<pre><code class="language-js">var regex = new RegExp("foo", "m")

console.log(regex.multiline) // true
</code></pre>
<h2 id="规范">规范</h2>
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<th scope="col">Specification</th>
<th scope="col">Status</th>
<th scope="col">Comment</th>
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<td>ECMAScript 3rd Edition. Implemented in JavaScript 1.2.</td>
<td>Standard</td>
<td>Initial definition.<br/>
    JavaScript 1.5: <code>multiline</code> is a property of a <code>RegExp</code> instance, not the <code>RegExp</code> object.</td>
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<td><a class="external" href="https://www.ecma-international.org/ecma-262/5.1/#sec-15.10.7.4" hreflang="en" lang="en" rel="noopener">ECMAScript 5.1 (ECMA-262)<br/><small lang="zh-CN">RegExp.prototype.multiline</small></a></td>
<td><span class="spec-Standard">Standard</span></td>
<td> </td>
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<td><a class="external" href="https://www.ecma-international.org/ecma-262/6.0/#sec-get-regexp.prototype.multiline" hreflang="en" lang="en" rel="noopener">ECMAScript 2015 (6th Edition, ECMA-262)<br/><small lang="zh-CN">RegExp.prototype.multiline</small></a></td>
<td><span class="spec-Standard">Standard</span></td>
<td><code>multiline</code> is now a prototype accessor property rather than an instance's own data property.</td>
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<h2 id="浏览器兼容性">浏览器兼容性</h2>
<p></p><div class="blockIndicator warning"><strong><a class="external" href="https://github.com/mdn/browser-compat-data" rel="noopener">We're converting our compatibility data into a machine-readable JSON format</a></strong>.
            This compatibility table still uses the old format,
            because we haven't yet converted the data it contains.
            <strong><a class="new" href="/zh-CN/docs/MDN/Contribute/Structures/Compatibility_tables" rel="nofollow">Find out how you can help!</a></strong></div>
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<a id="AutoCompatibilityTable" name="AutoCompatibilityTable"></a>
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<li class="selected"><a>Desktop</a></li>
<li><a>Mobile</a></li>
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<th>Feature</th>
<th>Chrome</th>
<th>Firefox (Gecko)</th>
<th>Internet Explorer</th>
<th>Opera</th>
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<td>Basic support</td>
<td><span style="color: #888;" title="Please update this with the earliest version of support.">(Yes)</span></td>
<td><span style="color: #888;" title="Please update this with the earliest version of support.">(Yes)</span></td>
<td><span style="color: #888;" title="Please update this with the earliest version of support.">(Yes)</span></td>
<td><span style="color: #888;" title="Please update this with the earliest version of support.">(Yes)</span></td>
<td><span style="color: #888;" title="Please update this with the earliest version of support.">(Yes)</span></td>
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<th>Feature</th>
<th>Android</th>
<th>Chrome for Android</th>
<th>Firefox Mobile (Gecko)</th>
<th>IE Mobile</th>
<th>Opera Mobile</th>
<th>Safari Mobile</th>
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<td>Basic support</td>
<td><span style="color: #888;" title="Please update this with the earliest version of support.">(Yes)</span></td>
<td><span style="color: #888;" title="Please update this with the earliest version of support.">(Yes)</span></td>
<td><span style="color: #888;" title="Please update this with the earliest version of support.">(Yes)</span></td>
<td><span style="color: #888;" title="Please update this with the earliest version of support.">(Yes)</span></td>
<td><span style="color: #888;" title="Please update this with the earliest version of support.">(Yes)</span></td>
<td><span style="color: #888;" title="Please update this with the earliest version of support.">(Yes)</span></td>
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<h2 id="See_also" name="See_also">相关链接</h2>
<ul>
<li><a href="Reference/Global_Objects/RegExp/global" title='global 属性表明正则表达式是否使用了 "g" 标志。global 是一个正则表达式实例的只读属性。'><code>RegExp.prototype.global</code></a></li>
<li><a href="Reference/Global_Objects/RegExp/lastIndex" title="lastIndex 是正则表达式的一个可读可写的整型属性，用来指定下一次匹配的起始索引。"><code>RegExp.prototype.lastIndex</code></a></li>
<li><a href="Reference/Global_Objects/RegExp/ignoreCase" title='ignoreCase 属性表明正则表达式是否使用了 "i" 标志。ignoreCase 是正则表达式实例的只读属性。'><code>RegExp.prototype.ignoreCase</code></a></li>
<li><a href="Reference/Global_Objects/RegExp/source" title="source 属性返回一个值为当前正则表达式对象的模式文本的字符串，该字符串不会包含正则字面量两边的斜杠以及任何的标志字符。"><code>RegExp.prototype.source</code></a></li>
<li><a href="Reference/Global_Objects/RegExp/sticky" title="sticky 属性反映了搜索是否具有粘性（ 仅从正则表达式的 lastIndex 属性表示的索引处搜索 ）。sticky 是正则表达式对象的只读属性。"><code>RegExp.prototype.sticky</code></a></li>
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